Harlequin Rasboras refusing to eat

This is a discussion on Harlequin Rasboras refusing to eat within the Cyprinids and Atherinids forums, part of the Freshwater and Tropical Fish category; -->
I was hoping jaysee, or someone else with that level of expertise would have gotten back to you by now. Any ammonia at all ...

I was hoping jaysee, or someone else with that level of expertise would have gotten back to you by now. Any ammonia at all is cause for concern. Combine that with 40 Nitrates, (50 being the limit in most references I've found, though, personally, I wish they all said 20 for a limit), & your fish may actually be in pain, which would curb their appetites. Corys are especially affected by ammonia, nitrites & nitrates, or any pH swing, that might accompany spikes in those. If it was me, I would do a 50% water change, trying to keep the water you put back in as close to the tank temp as possible, though a degree or 2 higher might be better, making sure to dose well with anti-chlorine before adding your water of course, using Prime especially if you have it; a lot of people seem to like it best from what posts I've seen.

Yeah, ammonia and nitrite will stress fish and stressed animals do not eat, so that makes sense. Nitrates are not something that concerns me. mine are routinely "high" like that. In any event, water changes would be good. you said you have been doing them, but what exactly have you been doing?

I performed a 40 % water change the day before I tested the tank. I will be performing another 40 % change as soon as I get home today. As strange as it sounds, I've never had 0 ammonia in any of my tanks. Its always been 0.25 or higher ( When Cycling).